Comparison of outcomes for short-neck and juxtarenal aortic aneurysms treated with the Nellix endograft versus conventional endovascular aneurysm sealing

Objective The objective of this study was to evaluate the results of the off-label use of the Nellix endograft (Endologix, Irvine, Calif) for the treatment of short-neck aneurysms and juxtarenal aortic aneurysms (JAAs) compared with the outcomes of patients with infrarenal abdominal aortic aneurysms treated in accordance with the manufacturer's instructions for use. Methods Data available from patients treated with the Nellix endograft from September 2013 to January 2016 were reviewed to create a case-control analysis (1:2). Fourteen elective patients with a short-neck aneurysm or JAA (<10 mm) and mild aortic neck angulation (<35 degrees) were included. As a control group, 28 elective patients who had been treated in accordance with instructions for use were included. Patients were matched for age, sex, aortic diameter, and aortic neck angulation. The final cohort group included 42 patients: 14 in the JAA off-label group (5 with aortic neck length ≤4 mm and 9 with necks of 5 to 10 mm) and 28 in the control group. Technical and clinical success, freedom from any secondary intervention, any type of endoleak, and aneurysm-related death were evaluated. Results There were no significant differences between the two groups in terms of comorbidity, intraoperative time, radiation time, contrast agent volume, and perioperative mortality and morbidity. Two patients of the JAA group subsequently underwent open repair (14%), both with aortic neck length <4 mm (2/5; 40%), for type Ia endoleak. Two of the control group also subsequently underwent open repair (7%). At a mean follow-up of 22 ± 3.9 months, freedom from any reintervention was 85% for the JAA off-label group vs 92% for the control group (log-rank test, P =.33). Conclusions The off-label use of the Nellix endograft for the treatment of JAA showed a higher rate of subsequent conversion to open repair for JAA patients (aortic neck length ≤4 mm), underlining the need for a proximal sealing zone. Longer term data are needed to verify the possible use of the Nellix endograft in selected short-neck aneurysms with aortic neck length >5 mm.